(4) is very plausible even if the study fails to find genetic variants associated with intelligence. Assuming intelligence is heritable at all, you don't need t

(4) is very plausible even if the study fails to find genetic variants associated with intelligence. Assuming intelligence is heritable at all, you don't need to understand the underlying genetic architecture to breed for it any more than neolithic farmers needed to understand the genetics of docile sheep to breed them. This has been known for a long time, but there has been no large scale, serious attempt to implement a eugenics program breeding for intelligence. I don't see how this research would change anything, successful or not, other than by getting the subject some attention in the news.